The present invention relates to the manufacture of tires. More particularly, it relates to techniques for the manufacture of tires on a support the shape of which is very close or even identical to the final manufactured shape of the tire.
U.S. Pat. No. 4,895,692 describes a tire mold having a rigid core which determines the inner shape of the tire; it also describes a process of assembling the tire with the use of such a mold. Such a mold can be considered "rigid", since this mold imposes upon the tire a molding space of a given volume. This volume is bounded on the outside by the shells of the mold and by the group of sectors molding the tread, and on the inside by the rigid core. The use of this mold leads to a vulcanization stage with quasi-imposed volume. It is also known that most of the molds currently used at the present time are molds having only the two shells which assure the molding of the outside of the sidewalls and a ring of sectors which assure the molding of the outside of the tread. The use of these molds upon vulcanization leads, in order to assure the molding, to the spreading out within the raw tire of a flexible bladder, so that it can be considered that the vulcanization takes place in this case with imposed pressure and not with imposed volume.